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3.1.8. Identifying Procedures for Conducting Container Vapor Flaring Operations. Before ASME tank maintenance tasks can be done, it may be necessary to evacuate propane liquid and flare the propane vapor. . In this module you will identify: Procedures for conducting vapor flaring operations .
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3.1.8 Identifying Procedures for Conducting Container Vapor Flaring Operations Before ASME tank maintenance tasks can be done, it may be necessary to evacuate propane liquid and flare the propane vapor. • In this module you will identify: • Procedures for conducting vapor flaring operations
NFPA 58 NFPA 58 2004 2001 7.3.2.4 4.3.2.3 Procedures for Conducting Vapor Flaring Operations Flaring is the process of burning LP-gas removed from storage containers in a controlled and safe manner. NFPA 58 requires that LP-gas be burned at least 25 feet from combustibles. Although venting vapor may be the simplest way to evacuate a container, it is not the safest, and not permitted in some areas.
Procedures for Conducting Vapor Flaring Operations Types of Flaring Burners Figure 1. Figure 2. Figure 3.
Procedures for Conducting Vapor Flaring Operations Types of Flaring Burners Figure 4a. Electronic Ignition Flare Tower Figure 4b. Top of Flare Tower Burning Propane from Cylinder
Procedures for Conducting Vapor Flaring Operations • The following procedures are limited to: • ASME tanks with capacities under 2,000 gallons • Removing most of the liquid in the container with a pump or compressor before the flaring operation begins • Using a suitable burner to flare the remaining propane in the container • Flaring the propane at the bulk plant
Procedures for Conducting Vapor Flaring Operations Figure 5. Recommended Site for Flaring Containers (At Bulk Plant)
Procedures for Conducting Vapor Flaring Operations It is important to select a burner with both a built-in shutoff and a regulator. This allows for adjustment of the output of the burner and prevents any excessive withdrawal from the tank being flared. Remember, excessive withdrawal could easily cause the tank to temporarily stop vaporizing enough gas to supply the burner. This condition may be noticed when a frost line appears on the container — yet sufficient liquid may remain to re-pressurize the container when it regains heat from surrounding air.
Procedures for Conducting Vapor Flaring Operations Gas Supply Line Figure 6. Supply Hose for Flaring Burner
Procedures for Conducting Vapor Flaring Operations • Gas Supply Line — The supply line should: • Be an approved propane hose (350 psig working pressure; 1,750 psig bursting pressure) • Be at least 20 feet long (15 feet for safety distance with 5 feet of "slack"). If the container is leaking, the burner may have to be located more than 15 feet from the container being flared • Have an excess-flow check valve installed on the inlet (container end) of the hose to limit the volume of gas released if the supply line breaks during the flaring operation
Procedures for Conducting Vapor Flaring Operations Burner Supports Figure 7. Flaring Burner Supports
Procedures for Conducting Vapor Flaring Operations • Flaring operations should incorporate the following safety practices and recommendations: • Flaring operations should never be left unattended and qualified personnel should continuously monitor flaring equipment and conditions. • If qualified personnel must leave the flaring operation for any reason, the operation should be shut down and the valve(s) on the container being flared should be closed.
Time to See If You Got the Key Points of This Module… • Complete the Review on page 10. • See if you are ready for the Certification Exam by checking off the performance criteria on page 11.
